Thylamys: Didelphidae) from Northwestern Argentina and Southern Bolivia, with the Description of a New Species of Tapeworm

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Endoparasites of Fat-Tailed Mouse Opossums (Thylamys: Didelphidae) from Northwestern Argentina and Southern Bolivia, with the Description of a New Species of Tapeworm

F. Agustin Jimenez Ruiz Southern Illinois University Carbondale, [email protected]

Janet K. Braun Sam Noble Oklahoma Museum of Natural History, [email protected]

Mariel Campbell University of New Mexico

Scott Lyell Gardner University of Nebraska - Lincoln, [email protected]

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Jimenez Ruiz, F. Agustin; Braun, Janet K.; Campbell, Mariel; and Gardner, Scott Lyell, "Endoparasites of Fat- Tailed Mouse Opossums (Thylamys: Didelphidae) from Northwestern Argentina and Southern Bolivia, with the Description of a New Species of Tapeworm" (2008). Faculty Publications from the Harold W. Manter Laboratory of Parasitology. 81. https://digitalcommons.unl.edu/parasitologyfacpubs/81

This Article is brought to you for free and open access by the Parasitology, Harold W. Manter Laboratory of at DigitalCommons@University of Nebraska - Lincoln. It has been accepted for inclusion in Faculty Publications from the Harold W. Manter Laboratory of Parasitology by an authorized administrator of DigitalCommons@University of Nebraska - Lincoln. J. Parasitol., 94(5), 2008, pp. 1098–1102 ᭧ American Society of Parasitologists 2008

ENDOPARASITES OF FAT-TAILED MOUSE OPOSSUMS (THYLAMYS: DIDELPHIDAE) FROM NORTHWESTERN ARGENTINA AND SOUTHERN BOLIVIA, WITH THE DESCRIPTION OF A NEW SPECIES OF TAPEWORM

F. Agustı´n Jime´nez, Janet K. Braun*, Mariel L. Campbell, and Scott L. Gardner The Harold W. Manter Laboratory of Parasitology, University of Nebraska State Museum, Lincoln, Nebraska 68588-0514. e-mail: [email protected]

ABSTRACT: The parasite fauna of 2 species of fat-tailed mouse opossums from northwestern Argentina is herein presented. Five species of helminths were found, i.e., Pterygodermatites kozeki, Hoinefﬁa simplispicula, Oligacanthorhynchus sp., and a new species of tapeworm, Mathevotaenia sanmartini n. sp. (Cyclophyllidea: Anoplocephalidae). The new species is characterized by a calyciform scolex, relatively few testes (32), and a long cirrus sac; it occurs in fat-tailed mouse opossums at localities above 4,000 m. Those characters make it different from 6 species known to occur in marsupials from the New World, and from other species occurring in armadillos and bats. Didelphoxyuris thylamisis, H. simplicispicula, and Oligacanthorhynchus sp. appear to occur in marmosas from the Yungas region. In contrast, both P. kozeki and M. sanmartini n. sp. appear to occur exclusively in the Puna.

The knowledge of the parasite fauna of marsupials (Didel- Puna in Argentina. Three individuals of T. pallidior were collected in phimorphia: Didelphidae) in the New World is biased towards the Puna of Bolivia. The list of localities is presented below, and for each species of marsupial collected the general locality is given first, both the largest and most common species of Philander and followed by latitude, longitude, and altitude (m). Numbers of individ- Didelphis (Wolfgang, 1951; Aldes, 1995; Vicente et al., 1997; uals examined for parasites are given in parentheses. Silva and Costa, 1999; Gomes et al., 2003). A search of the Collecting localities for T. pallidior include (Fig. 1): Argentina: Ca- literature shows that most of the detailed studies have been tamarca: Tinogasta, 34.6 km west of Fiambala´ (by road) 27Њ42Ј15.5ЉS, Њ Ј Љ Ϯ focused on those species occurring in either the northern hemi- 67 52 58.0 W, 2,395 8.6 m (3); 57 km west of Fiambala´ (by road), 27Њ47Ј40.5ЉS, 68Њ03Ј42.9ЉW, 3,053 Ϯ 8 m (3). Jujuy: Susques, 8.2 km sphere or the eastern coast of South America, and that little south of Sey (by road), 24Њ00Ј48.8ЉS, 66Њ30Ј52.8ЉW, 4,167 Ϯ 10 m (6). knowledge exists about the parasite fauna of the fat-tailed Salta: La Poma, 16 km south, 1.8 km west of Barrancas, along Rıó de mouse opossums (Thylamys spp.) in the central Andes. For the las Burras, 23Њ24Ј58.2ЉS, 66Њ12Ј23.0ЉW, 3,521 Ϯ 8.6 m (3). Bolivia: rest of the 15 genera and 77 species of didelphiomorphs in the Cochabamba: 5.7 km southeast of Rodeo, Curubamba, 17Њ40Ј31ЉS, 65Њ36Ј04ЉW, 4,000 m (3). Neotropics (Gardner, 2005), there are few helminthological re- Individuals of T. venustus were collected from 4 localities, including cords. For example, up to the present time, only 5 species of (Fig. 1): Argentina: Jujuy: Dr. Manuel Belgrano, 5 km north of San nematodes are known from fat-tailed mouse opossums in north- Salvador de Jujuy (by road), 24Њ07Ј35.2ЉS, 65Њ17Ј47.6ЉW, 1,414 Ϯ 8.5 ern Argentina and Bolivia (Navone et al., 1990, 1991; Gardner m (1); Las Capillas, 24Њ05Ј29.0ЉS, 65Њ10Ј33.0ЉW, 1,173 Ϯ 8.6 m (1); Њ Ј Љ and Hugot, 1995; Ramallo and Claps, 2007). Santa Ba´rbara, 24.8 km east of Santa Clara (by road), 24 17 47.4 S, 64Њ29Ј05.6ЉW, 1321 Ϯ 6.1 m (2); 5 km east of El Palmar, 24Њ06Ј08.8ЉS, In the present work, we summarize the findings on the hel- 64Њ33Ј14.9ЉW, 794 Ϯ 11.1 m (1). minth fauna of 2 species of fat-tailed mouse opossums from All marsupials were collected with the use of Sherman௢ live traps Argentina and integrate some of the results of our previous baited with a mixture of oatmeal, vanilla, tuna, and sardines, or snap expeditions to the highlands of Bolivia. Specimens of Thylamys traps baited with peanut butter. Traps were placed in suitable habitat venustus (Thomas, 1902) and Thylamys pallidior (Thomas, each evening and checked at first daylight the following morning. De- tails of each mammal collected were recorded in a field-collection cat- 1902) were collected from 8 localities in 3 provinces of Argen- alog book and in the trapping data book, which are maintained in the tina, including Salta, Jujuy, and Catamarca, and 1 locality in Department of Mammalogy, Sam Noble Oklahoma Museum of Natural the department of Cochabamba in Bolivia. Animals were col- History (OMNH), University of Oklahoma (Norman, Oklahoma), or for lected from habitats corresponding to the Yungas forest, Pre- the Bolivian material, data are maintained in both the Museum of South- puna, and Puna (Cabrera and Willink, 1973). western Biology, the University of New Mexico (Albuquerque, New Mexico) and the Harold W. Manter Laboratory of Parasitology We report 5 species of metazoan endoparasites from the in- (HWML), University of Nebraska State Museum (Lincoln, Nebraska). dividuals necropsied in the field, including species of Ptery- Additional details of trapping localities can be found in field notes of godermatites Wedl, 1861; Didelphoxyuris Gardner and Hugot, the expedition that refer to specimens of mammals maintained at the 1995; Hoineffia Diaw, 1976; Oligacanthorhynchus Travassos, OMNH, and specimens of parasites from those mammals in the HWML. 1915; and Mathevotaenia Akhuyman, 1946. The present study Mammal voucher specimens are deposited in the following institutions: Department of Mammalogy, OMNH; Coleccioń de Mamı´feros Lillo, provides information on parasites from fat-tailed mouse opos- Universidad Nacional de Tucumań, Tucumań, Argentina (CML); and sums collected during our field expedition to northwestern Ar- the Coleccioń de Mamı´feros, Museo de Ciencias Naturales ‘‘Bernardino gentina in the Austral fall (March and April) of 2006. Rivadavia,’’ Buenos Aires, Argentina (MACN). Some complete digestive tracts were fixed in the field at the time of collection, stored in 10% formalin, and examined in the laboratory with MATERIALS AND METHODS a dissecting microscope. In the field, each organ of the digestive system Fifteen individuals of Thylamys pallidior and 5 of Thylamys venustus was examined separately with an Optivisor௢ (Donegan Optical Com- were collected in 9 localities from habitats in the Yungas, Prepuna, and pany, Lenexa, Kansas). Nematodes found were killed in concentrated glacial acetic acid (GAA), 70% ethanol (EtOH), or 10% formalin. Tape- worms were placed in distilled water until they relaxed and were killed Received 16 August 2007; revised 18 January 2008; accepted 21 Jan- and fixed in either 70% EtOH or 10% formalin. Acanthocephalans were uary 2008. relaxed in cold water overnight. All worms were stored in the same *Mammalogy Division of The Sam Noble Oklahoma Museum of Nat- medium in which they were killed, except for those killed in GAA and ural History, 2401 Chautauqua Avenue, Norman, Oklahoma 73072. water, which were then transferred for storage and transport into 70%

1098 JIME´ NEZ ET AL.—ENDOPARASITES OF FAT-TAILED MOUSE OPOSSUMS 1099

atodes Didelphoxyuris thylamisis Gardner and Hugot, 1995 (Oxyuridae) collected from the cecum (prevalence 100%, HWML63385 through HWML63388; CHMLP5729, and CNHE5985), and Hoinefﬁa simplicispicula Navone, Suriano and Pujol, 1991 (Viannaiidae), found in the small intestine (prevalence 20%, HWML63395). Finally, Oligacathorhynchus sp. (Acanthocephala: Oligacanthorhynchidae) was collected from the small intestine (prevalence 20%, HWML70021).

DESCRIPTION Mathevotaenia sanmartini n. sp. (Figs. 2–6) General (based on 7 whole mounts): Cyclophyllidea: Anoplocephal- idae. Moderately long tapeworms 91–212 mm (n ϭ 3) in total length with more than 200 segments or proglottids. Maximum width at gravid segments 1,123–2,427, 1,664 (24%, n ϭ 35). Scolex unarmed, cup- shaped or calyciform, conspicuously wider than neck 843–1,246, 1,002 (19%) in length 824–1,415, 1,011 (22%) wide (Fig. 2). Suckers oval with heavy muscular walls 302–399, 341 (5%, n ϭ 28) long by 236– 336, 298 (9%, n ϭ 28) wide, each sucker inside a pocket that opens FIGURE 1. Collecting localities in Argentina and Bolivia. (1) 34.6 externally at most anterior part of structure through a slit (Fig. 2). Neck km west of Fiambala´ (by road); (2) 57 km west of Fiambala´ (by road); 950–1,848, 1,316 (27%) long and 374–805, 646 (24%) wide. Primordia (3) 8.2 km south of Sey (by road); (4) 16 km south, 1.6 km west of of reproductive organs (anlagen) visible at 58th proglottid (56th, 58th, Barrancas, along Rıó de las Burras; (5) 5.7 km southeast of Rodeo, 60th). Testes clearly formed at proglottid 31–48, 39 (19%, n ϭ 7), and Curubamba; (6) Las Capillas; (7) 24.8 km north of Santa Clara (by gravid proglottids first visible at 144th segment (111th, 158th, 168th). road); (8) 5 km north of San Salvador de Jujuy; (9) 5 km east of El Mature proglottids 245–760, 459 (26%, n ϭ 51) long and 805–1,721, Palmar. 1,277 (20%, n ϭ 51) wide; length–width ratio of 1:1.9–1:7. Gravid proglottids 469–1,662, 946 (33%, n ϭ 35) long by 1,123–2,427, 1,664 (24%, n ϭ 35) wide, length–width ratio 1:1.3–1:1.7. Terminal gravid proglottids 1,144–3,272, 2,049 (30%, n ϭ 24) by 970–2,394, 1,512 aqueous v/v ethyl alcohol. Some specimens were preserved in vials (32%, n ϭ 24), length–width ratio 1:0.3–1:1.9. Genital pores alternate filled with 95% aqueous v/v EtOH, or placed in cryotubes, frozen in irregularly. Genital ducts crossing excretory canals dorsally (Fig. 3). liquid nitrogen, transported back to the laboratory in liquid nitrogen, Female reproductive system: Ovary in medial portion of proglottid, Ϫ and stored at 85 C in an ultralow freezer in the HWML. Abbreviations bilobed with up to 13 lateral lobules, never reaching excretory canals. of museums from which specimens were borrowed or studied include Ovary 376–708, 551 (15%, n ϭ 32) long and 166–331, 238 (18%, n ϭ the Coleccioń Nacional de Helmintos (CNHE) of the Universidad Na- 32) wide, starts on segments 42–64, 55 (16%, n ϭ 7). Oviduct connects cional Autońoma de Me´xico, Me´xico, the Harold W. Manter Laboratory ovarian isthmus to Mehlis’ gland. Vitelline gland in posterior half of of Parasitology (HWML), the Museo de Historia Natural, Departamento proglottid; few lobes projecting posteriad, connecting posteriorly to de Zoologıá de Invertebrados, Argentina (CHMLP), and the United semispherical Mehlis’ gland. Mehlis’ gland connected to fertilization States National Parasite Collection (USNPC). Specimens used for com- duct, which opens into thin vaginal duct. Vaginal duct surrounded by parative purposes included Didelphoxyuris thylamisis Gardner and Hu- glands (Figs. 3, 4). Oviduct arising from ovarian isthmus. No seminal got, 1995 (HWML39072, HWML39073, HWML63352–81), Mathevo- receptacle present; vagina anterior to cirrus pouch. Eggs in egg capsules taenia argentinensis Campbell, Gardner and Navone, 2003 (Fig. 5), clustered in parenchyma and occupying most of proglottid. (HWML17712), and Mathevotaenia bivittata (Janicki, 1904) Oncospheres 15–34, 23 (16%, n ϭ 158) wide, 15–38, 28 (16%, n ϭ (HWML17712). 158) long, usually wrinkled as possible artifact of fixation and manip- Nematodes were cleared for study in lactophenol. Tapeworms were ulation post mortem. Egg capsules 27–57, 39 (16%, n ϭ 158) by 15– stained in Semichons’ carmine and mounted on a microscope slide in 38, 28 (16%, n ϭ 158). Embryonic hooks 9–15, 12 (9%, n ϭ 65). Damar gum. Cross sections of the specimens were made with a stain- Male reproductive system: Testes from 26 to 41 in number, 32 (12%, less-steel razor blade. Drawings were made with a Wild microscope n ϭ 40 proglottids), arranged in 2 lateral fields between both ovary and equipped with a drawing tube. Measurements were made with the use vitelline gland and between lateral excretory canals. Testes first seen ௢ of a Zeiss Ultraphot microscope and digital measuring software (Jan- forming at segment 39 (31st–48th, n ϭ 7), 54–96, 77 (14%, n ϭ 151) ௢ del Sigma Scan Pro , San Rafael, California; Albinger et al., 1995). long and 44–96, 71 (20%, n ϭ 151) wide. Vas deferens starting slightly Measurements are given in micrometers. For each character, the range posterior and ventral to vitelline gland; directed anteriad running ven- is given first, followed by sample mean and coefficient of variation as trally to ovary over midline, turning porally, becoming highly convo- a percentage (Sokal and Rohlf, 1995). If sample size for a character luted after passing ovary. Cirrus pouch 116–239, 175 (21%, n ϭ 37) studied was different from number of specimens examined, this also is long by 62–96, 77 (9%, n ϭ 37%) wide. Cirrus spinose, convoluted given. when invaginated (Fig. 6).

RESULTS Taxonomic summary Four species of parasites were found in the necropsied fat- Symbiotype: Thylamys pallidior (Thomas, 1902) OMNH 34911. Type locality: Argentina: Jujuy: Susques, 8.2 km south of Sey (by tailed opossums. Here we present the description of a new spe- road), 24Њ00Ј48.8ЉS, 66Њ30Ј52.8ЉW, 4,167 Ϯ 10 m (31 March and 1 cies of tapeworm and the accounts for 4 species, 1 acantho- April 2006). Prevalence 75%, n ϭ 4 (Fig. 1). cephalan and 3 nematodes. Among these Pterygodermatites Other localities: Bolivia: Cochabamba: Curubamba, 7.5 km southeast kozeki (Chabaud and Bain, 1981) (Rictaluriidae) was found in of Rodeo (by road), 17Њ40Ј31ЉS, 65Њ36Ј04ЉW, 4,000 m (24 and 26 July 1993). Prevalence 75%, n ϭ 4. the small intestine and duodenum of Thylamys pallidior (prev- Specimens deposited: Holotype CHLP5727, paratypes alence 83%, HWML63390–91 and CHMLP5730). The rest of HWML70037–HWML70040, CHLP5728. the worms occurred in Thylamys venustus, including the nem- Habitat: Small intestine. 1100 THE JOURNAL OF PARASITOLOGY, VOL. 94, NO. 5, OCTOBER 2008

FIGURES 2–4. Mathevotaenia sanmartini n. sp. 2. Scolex showing the calyciform structure holding the suckers. 3. Mature proglottids, showing the relative positions of ovary, testes, and vitellaria. 4. Cross section of a mature proglottid, showing the ventral position of the excretory canals relative to the cirrus pouch. JIME´ NEZ ET AL.—ENDOPARASITES OF FAT-TAILED MOUSE OPOSSUMS 1101

FIGURES 5 AND 6. Micrographs of Mathevotaenia sanmartini n. sp. 5. Egg showing oncosphere and envelope. Scale bar ϭ 50 ␮m. 6. Poral side of a gravid proglottid, showing cirrus pouch and everted cirrus. Scale bar ϭ 100 ␮m.

Etymology: The species is named after General Jose´ de San Martıń, and other areas, particularly as the host species, T. pallidior, ‘‘El Libertador’’. exhibits the broadest geographic and elevational range in the Remarks genus. The known collection records for T. pallidior show this Mathevotaenia sanmartini n. sp. is unique in having a calyciform species ranges from southern Peru to Chubut Province, Argen- scolex, an average of 32 testes per segment, and a relatively long cirrus tina, where it occupies many diverse habitats, including the Al- pouch, which crosses the excretory canals. Mathevotaenia sanmartini tiplano, Puna, Monte Desert, Southern Andean Steppe, and Pat- can be recognized as distinct from both M. bivittata and Mathevotaenia agonia Steppe from sea level to more than 4,000 m. This ces- didelphidis (Rudolphi, 1819) in having a much longer cirrus sac and an average of 32 testes per segment versus 13 and 20 per segment, re- tode–host–habitat association is similar on a biological sense to spectively. Mathevotaenia sanmartini can be recognized as distinct from that reported by Gardner and Campbell (1992) for the restricted M. argentinensis in having a much longer cirrus sac and total length of distribution in the Yungas of Bolivia for species of Linstowia the strobila. Interestingly, M. sanmartini has a cirrus sac that is rela- Zschokke, 1988 in marsupial species of Thylamys and Mono- tively much longer than all other species of the genus in the Neotropics, thus allowing the cirrus sac to cross the excretory canals. In other spe- delphis. Additionally, the possible synapomorphy of the relative cies, including M. argentinensis, the cirrus sac is short and never crosses length of the cirrus sac in M. sanmartini and the Australian the excretory canals. In this respect, M. sanmartini is more similar to fauna deserves more attention (for example, see linstowiid dis- other anoplocephalids present in Australian marsupials. At the present time, only 5 species of Mathevotaenia have been re- cussion by Gardner and Campbell, 1992). corded from didelphid marsupials in South America. In Argentina, the The records for the nematodes Pterygodermatites kozeki, D. cestodes M. argentinensis and M. bivittata were collected from both thylamisis, Hoineffia simplicispicula, and the unidentified spe- Didelphis albiventris Lund, 1840 and Micoureus cinereus Temminck, cies of Oligacanthorhynchus may represent range extensions. 1824, respectively (Campbell et al., 2003). Those specimens, as well as most other species of Mathevotaenia in the Neotropics, were collected Pterygodermatites kozeki presents a distribution pattern similar from localities at relatively low altitudes. to that of M. sanmartini in that it has been found in localities along the Puna, ranging from Colombia to Mendoza Province, DISCUSSION central Argentina. Nevertheless, Ramallo and Claps (2007) re- Mathevotaenia sanmartini occurs in marsupials inhabiting cently reported finding this species at lower altitudes. The lo- only high-altitude habitats of the Altiplano and Puna, having cality of the record from Argentina reported herein from Ca- been collected from 2 sites at over 4,000 m more than 700 km tamarca Province is geographically located between the 2 ex- apart. Interestingly, the other species in the genus that occur in tremes for the distribution of this species. Finally, it appears marsupials are known only from low-altitude habitats, with the that Oligachanthorhynchus sp., H. simplicispicula, and D. thy- most widespread (M. bivittata) ranging from Panama´ to Argen- lamisis may be associated more with tropical or subtropical tina (Campbell et al., 2003). Whether this is a reflection of the localities, such as the Yungas, which extends from a southern effort of field biologists collecting mammals from these habitats limit in Argentina north through Bolivia and into Peru. Didel- or is an actual biological characteristic of this cestode/host as- phoxyuris thylamisis was previously recorded from the Yungas sociation remains to be tested with additional sampling in these of Bolivia, and there are several records of acanthocephalans 1102 THE JOURNAL OF PARASITOLOGY, VOL. 94, NO. 5, OCTOBER 2008 infecting marsupials in the forests and savannahs of South CAMPBELL, M. L., S. L. GARDNER, AND G. T. NAVONE. 2003. A new America. species of Mathevotaenia (Cestoda: Anoplocephalidae) and other tapeworms from marsupials in Argentina. Journal of Parasitology The parasite fauna of fat-tailed mouse opossums appears to 89: 1181–1185. be depauperate relative to that of opossums examined from lo- GARDNER, A. L. 2005. Order Didelphimorphia. In Mammal species of calities in tropical habitats, thus far consisting of 7 species from the world: A taxonomic and geographic reference, D. E. Wilson which only M. sanmartini appears to be specific. Two species and D. M. Reeder (eds.). The Johns Hopkins University Press, Bal- timore, Maryland, p. 3–18. of helminths occur in T. pallidior (M. sanmartini and P. kozeki), GARDNER, S. L., AND J. P. HUGOT. 1995. A new pinworm, Didelphox- and 3 infect T. venustus (D. thylamisis, H. simplicispicula, and yuris thylamisis n. gen., n. sp. (Nematoda: Oxyurida) from Thyla- Oligacanthorhynchus sp.). In our survey, we found no parasites mys elegans (Waterhouse, 1839) (Marsupialia: Didelphidae) in Bo- being shared between these 2 species of fat-tailed opossums. livia. Research and Reviews in Parasitology 55: 139–147. Size, extent of range of host, and suitability of intermediate ———, AND M. L. CAMPBELL. 1992. Parasites as probes for biodiver- sity. Journal of Parasitology 78: 596–600. hosts in high-altitude habitats in South America may account GOMES, D. C., R. P. D. CRUZ,J.J.VICENTE, AND R. M. PINTO. 2003. for the poor diversity in helminths that we documented in these Nematode parasites of marsupials and small rodents from the Bra- mammals; however, much more work is needed to verify these zilian Atlantic rain forest in the State of Rio de Janeiro, Brazil. observations. Revista Brasileira de Biologia 20: 699–707. NAVONE,G.T.,D.M.SURIANO, AND C. A. PUJOL. 1990. Neohilgertia venusti gen. n. sp. n. (Nematoda: Oxyuridae) from Thylamys ven- ACKNOWLEDGMENTS ustus cinderellus (Thomas) Reig, Kirsch & Marshall, 1985 (Mar- We acknowledge National Science Foundation (NSF) grants DEB 01- supialia: Didelphidae) in Burruyacu, Tucuman, Argentina—Sys- 03711 to M.A. Mares and J.K.B. and NSF grant DEB9024816 to tematic position and possible evolution. Memo´rias do Instituto Os- S.L.G., and the Hagan Fund, the University of Nebraska State Museum, waldo Cruz 85: 185–189. for support of field work for F.A.J. The Harold W. Manter Laboratory ———, ———, AND ———. 1991. Travassostrongylus yungaensis n. Development Fund is also acknowledged for providing support of our sp. and Hoineffia simplicispicula n. sp. (Nematoda: Trychostron- work in the H. W. Manter Laboratory. We thank R. M. Barquez and gyloidea) from Thylamys venustus and Lutreolina crassicaudata his students at the Universidad Nacional de Tucumań, Tucumań, Ar- (Marsupialia: Didelphidae) in the Northwest Argentina. 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